Grinding machine



Nov. 20, 1945.

W. G. WESSMAN GRINDING MACHINE} Filed Aug. 10, 1943 15 Sheets-Sheet 1INVENTOR WaZ ze BY r G. Wes smczn 'o NEY Nov. 20, 1945. w. e. WESSMANGRINDING MACHINE 15 Sheets-Sheet 2 Filed Aug. 10, 1943 INVENTOR Wa ZzerG. Wessma'n BY A No v. 20, 1945. W.\G. WESSMAN GRINDING MACHINE FiledAug. 10, 1943 15 Sheets-Sheet 3 INVENTOR Walter G. Wessman BY Nov. 20,1945. w, WESSMAN GRINDING MACHINE 15 Sheets-Sheet 5 Filed Aug. 10, 1943lllll MW hm mm mm Nam INVENTOR WaZzer BY G.Wessma?2 7 T R EY Nov- 20, 1w. s. WESSMAN GRINDING MACHINE 15 Sheets-Sh eet 6 Filed Aug. 10, 1943lNVENTOR Zter G. Wessmcm Nov. 20, 1945. w.. G. WESSMAN GRINDING MACHINEFiled Aug. 10, 1943 15 Sheets-Sheet 8 vmw 22- G. Wessman' lNVENTdR Nov.20, 1945. we. WESSMAN GRINDING MACHINE Filed Aug. 10, 1943 15Sheets-Sheet 9 INVENTOR Her 6. Wessmaz? Nov. 20, 1945.

G. WESSMAN GRINDING MACHINE Filed Aug. 10, 1943 15 Sheets-Sheet 10 RNmmw 6w MWN wmw wmw wmw NNIT 3 mmH INVENTOR Wa Zzer G. Wessman Nov. 20,1945. w. G. WESSMAN GRINDING MACHINE Filed Aug. 10, 1943 15 Sheets-Sheet11 ORNEY Nov. 20, 1945. W.\G WESSMAN I I 2,389,224

GRINDING MACHINE Filed Aug. 10, 1945 15 Sheets-Sheet 12 g W250 I 2/; LM93 ;29/ ,/288 293 l INVENTOR I v VaZfer G. Wes'sman I ORNEY f Nov. 20,1945. w s. WESSMAN GRINDING MACHINE Filed Aug. 10, 1943 15 Sheets-Sheet13 ORNEY n a m S a W G T.

INVENTOR Walte BY I I Nov. 20, 1945.

Was, WESSMAN 2,389,224

GRINDING MACHINE Filed Aug 10, 1945 15 Sheets-Shej; 14

e /40 300 3 di j 297 299 5 El i 1 I 3 5 -26/a 3/4 .Fig. 28

F 2 7 INVENTOR WaZzer' G. Wessman Patented Nov. 20, 1945 UNITED STATESPATENT OFFICE GRINDING MACHINE Walter G. Wessman, Fairfield, Conn.Application August 10,1943, Serial No. 498,058

35 Claims.

This invention relates to new and useful improvements in abradingapparatus and has particular relation to a grinding machine adapted tobe used for grinding, lapping and polishing operations.

An object of the-invention is to provide a grinding machine adapted todo multi-angle grinding with one set-up and without disturbing such set-Among the other objects of the invention are the provision of a machineadapted for operation by unskilled help to do precision grinding, to domulti-angle grinding and/or profile grinding, both internal andexternal. in one set-up without the use of especially shaped grindingwheels.

Other objects and advantages of the invention will become apparent froma consideration of the following detailed description taken inconnection with the accompanying drawings wherein satisfactoryembodiments of my invention are shown. However, it is to be understoodthat the invention is not limited to the details disclosed but includesall such variations and modifications as fall within the spirit of theinvention and the scope of the appended claims.

In the drawings;

Fig. l is a front elevational view of the upper portion of a pedestaltype of machine made in accordance with the present invention;

Fig. 2 is a top plan view of said machine;

Fig. 3 is an end elevational view thereof the view being taken aslooking from the right in Fig. 1;

Fig. 4 is a transverse sectional view taken as along the plane of theline 44 of Fig. 1;

Fig. 5 is a horizontal sectional view taken as along the plane of theline 5-5 of Fig. 1;

Fig. 6 is a horizontal sectional view taken as along the plane of theline 6-6 of Fig. 1;

Fig. 7 is a plan view on a larger scale of the work holding head of themachine;

Fig. 8 is a view partly in front elevation and partly in section of thehead of Fig. 7;

Fig. 9 is an end elevational view of such head the view being taken aslooking from the left in Fig. 7;

Fig. 10 is a detail view as looking from the line ill-10 of Fig. 9 andshowing in elevation a looking means employed;

Fig. 11 is a similar view of the same means but the view is taken aslooking from the line lll l of Fig. 9;

Fig. 12 is a View of a bearing means alone;

Fig. 13 is a plan view on an enlarged scale of a slid employed;

Fig. 14 is a side elevational view of said slide on said enlarged scaleand showing some associated parts;

Fig. 15 is an end elevational view of said slide the view being taken aslooking from th left in Fig. 14;

Fig. 16 is a top plan view of said slide with parts broken away andshowing the same as adapted for profile grinding;

Fig. 17 is a transverse sectional view taken as along the line "-41 ofFig. 13;

Fig. 18 is a front elevational view of the machine of the invention asincorporated in a bench type of machine;

Fig. 19 is a top plan view of the bench type of .machine of Fig. 18;

Fig. 20 is an end elevational view of said machine, the view being takenas looking from the right in Fig. 18;

Fig. 21 is a vertical sectional View through the machine, the view beingtaken as along the plane of the line 2|-2l of Fig. 18;

Fig. 22 is a horizontal sectional view, the same being taken as alongthe plane of the line 22-22 of Fig. 18;

Fig. 23 is a transverse sectional view 23-23 of Fig. 22;

Fig. 24 is a diagrammatic view showing a grinding operation beingperformed with my present machine;

Fig. 25 is similar view showing the motions of parts as involved in thegrinding of the work shown in Fig. 24;

Fig. 26 is a. View similar to Fig. 24 but illustrating the use of theinvention in connection with a different piece of work; 7

Fig. 27 is the diagram of the motions of the machines parts in thegrinding of the piece of work of Fig. 26-;

Fig. 28 is a sectional on the line View illustrating an internalgrinding job;

Fig. 29 is a sectional view illustrating another internal grinding job;

Fig. 30 is another sectional View illustrating a more complicatedinternal grinding job;

Fig. 31 is a detail sectional view illustrating a further adjustment ofthe machine of the invention; and

Figs. 32, 33, 34, and 35 are sectional views of dies which are groundinternally with my present machine.

Referring in detail to the drawings and at first more particularly tothe form of the invention as shown in Figs. 1 through 17, my improvedmachine as shown includes a base or pedestal generally designated Illand including a lower portion l and an upper portion or machine bed 2.Portions II and i2 have engaging flange portions I3 through which arepassed bolts l4 whereby the pedestal portions are secured to oneanother.

In the forward portion of its upper side the bed I2 is provided with aflat way l5 and a V- way l6 (see particularly Fig. 4) and mounted onsuch portion of the bed and movable along said ways is a table generallydesignated I! and provided witlmportions, as shown, including the V-shaped block [8 entering the V-way 16. for guiding movement of suchtable. A depending skirt I!) about the edge of the table vent theentrance of emery or other dust into, the. mentioned ways.

Means are provided for manually moving the.

l1 serves to preej table in the direction of its length. Such means. 7

(see Figs. 4 and 6) includes a leverm'ean-s 20 having a hub 2| pinned at22 or otherwisem-aide fast to a shaft 23 journaled in bearings 24 and25in a, forward wall 26 anda web 21 of the bed l2. Bearing 24 ismadefast'to said wall 26-as by being secured in place by bolts or othermeans 28'. A- sprocket 29isfast to shaft 23 being keyed thereto at 30-or otherwise made to turn therewith. Additional sprockets 3| and 32 areturnable about said shaft as a mount and center and such sprockets aresecured to oneanother by'bolts 33. All of the three named sprockets arelocated on shaft 23 between the bearing 25 and a collar 34 fixed to theshaft in any suitable manner;

Journaled inthe bed |-'2-' inspaced but parallel relation to shaft 23 isa second shaft 35 having sprockets 36, 31 and which the sprockets 36 and31 aresecured together for unitary turning movement as by bolts or thelike 39-. Inthedescribed construction the sprocket 36 is oflargerdiameter than but is aligned with sprocket 29, while sprocket 31. is ofsmaller diameter thanet- 32, and sprockets 3| and 38' are of the samediameter and are in alignment.

Sprocket chains 49-, 4| and42-are trained over the pairs of' alignedsprockets 36 and 29, 31. and 32 and 38 and 3|, respectively. On turningof lever means-2-|l the shaft'23 willbe turned and'will impart the samemovement to sprocket 29 which through chaindll will cause' turning ofthe sprocket 36-. The latter-beingbolted or otherwise secured tosprocket 31 the sprockets36 and'3T' will turn as a unit and result inchain 41 being driven to in turn drive thesprocket 32. As sprocket 32 isfast with sprocket 3| the latter will be driven andwill feed; the chain42 and thus drive the sprocket 38 which is free, of sprockets 36 and 37aswell as of the shaft 35.

The described sprocket and sprocket chain, structure is for impartingmovement to the machine table I1. Such table, on its undersideintermediate its ends is provided'witha lug or pro.- jection 43 to whichthe upper flight of'the chain His-secured (see Fig. 4'). It will. be.clearthat. owing to the variationsin the diametersof the sprocketsemployed, the chain. 42 may be moved manually at a very low speed andsoon manipulation of the lever. means. 20 minute. movements, of greataccuracy, may be manually impartedjt'o. the table Preferably oilapplying rollers 4'4 and 4 5-are providedfor applying lubricantto the,lower surfaces of the-table portions engagi'ngwith the ways l5 and I6 atthe upper side of. machine bed l2.

Bolts-46 having'their heads disposedfina $1015.41 extendinglongitudinally of: the table ILTto serve.

38 turnable thereon and of to secure blocks 48 to such table. Clearlythese blocks may be adjusted relatively in the direction of the lengthof the slot 47 and each of the blocks 48 carries a screw 49 adapted foradjustment through the block. The bolts 49 are aligned with a lug 50 onthe machine bed l2 and such lug is in fact located between such bolts.With this arrangement it will be understood that on adjustment of theblocks 48 and of the screws 49 one or the other of such screws willengage the stop lug 53 as the table If!- is moved in one direction orthe other.-

Thus the mentioned lugs, blocks and screws provided adjustable means forlimiting move- -ments of the table by the lever means 20 and thesprocket and chain mechanism previously described. It will be understoodthat in any setup the blocks 48 and screws 49 are properly adjusted' andset and that thereafter as the table butis; aligned with sprockis movedback and forth the lug 50 will be engaged first by one of the stopscrews and then the other'as the table movement is reversed. The chainand sprocket means may be a pulley and belt arrangement if desiredalthough the chain and sprocket is more positive and also gives a smoothsteady movement to the table.

Means are provided for taking up slack in the respective chains 40, 4|and 42. To this end, idler sprockets 5|, 52 and 53 are mounted withinthe bed |2 in engagement with the lower flights of thechains 4| and"respectively. Sprockets' 5| and 53 are mounted on the correspondingarms of bell-cranks 54. and 55. pivoted on a shaft 56'. Connected withthe other arms of said bellcrank are rods 5! and58f passing through one.end of bed l2 andprovided' with nuts 59 adapted to be tightened to rockthe bell-cranks on the shaft 56 and thus carry the sprockets 5| and 53upwardly totighten the chains 40 and'42.

Sprocket 52 is mounted onan arm 6|)v turnable about'a shaft 6| with anarm 62 to the lower end of which is connected the inner end of a rod 63passing through the mentioned end wall of the bed l2 and beyond thelatter provided with nuts 64. With this arrangement chain 4| may betightened on tightening of' the nuts 64 to draw portion of'the slot therod 63 further through the. end wall of bed 2 and thereby rock the arms60 and 62 about shaft 61 forcing idler 52 upwardly against the lowerflight of said chain.

In its upper side table IT isv provided with a V'-Tslot 55extendinglongitudinally thereof and comprising a combination of a V-slotand a T- slot. Such slot. in. its. outer or. upper portion is in theform of a V while its-inner portion is an inverted T in transversesection. Disposed on the upper side-of the table. I1 is a base 66 (seeFigs. 1, 2,, 4,114 and115) including a plate-like portion 6'! resting onthe table. Bolts 68 have their heads disposed" in the inverted T-shaped6.5. and. pass upwardly through the plate-like portion 67 at the uppersideof which they are provided with nuts. 69.

These bolts pass throughkey-like members. 10

(see particularly Figs. 4, 14 and 15) entering,

partly'into grooves in the underside of portion 61 and having wedge orV-shaped portions entering the corresponding. portions of the slot Withthis arrangement it will be clear that on loosening of the nuts 69 thebase 66' may be moved. longitudinally of the table I! along the slot55'. On tightening of said nuts the base'66 will be drawn against theupper side of the table and the. keys; Ill: will. be, forced tight. intothe V- shaped portion o'f'slot 65 thus securing and aligning the base 68with respect to the V-shaped block I8 of table I! to insure movement andlocation of the centers parallel to the, V-Ways I6 in bed I2.

Base 86 includes a central upwardly directed annular portion I!graduated about its upper edge with thescale 12 marked thereon beginningat zero, as shown and building up from each side of said zero. The basehas an annular slightly tapered socket I3 therethrough and such socketbeing tapered is of slightly greater diameter at the upper side of thebase and is concentric with the raised central portion 'II of the base.

, Mounted on base 68' (see Fig. 1) is a slide generally designated I4and mounted on said slide and shown in angular relation thereto isanother but similar slide generally designated I5. Since these slidesare, with certain exceptions hereinafter fully pointed out, identical inconstruction a detailed description of but one will be given. Withparticular reference to Figs..l3, 14, 15 and 17 it will be noted thatthe slide I4 includes a bottom cover plate I6 and a swivel slide 83 fromwhich depends a slightly tapered projection 11 passing through a snuglyfitted tapered hole 16a in said plate I6 and disposed in the socket oropening I3 in base 66.

Projection 1'! includes upper and lower portions I8 and I9 (they are ofthe construction of projection I29 of Figs. 8 and 9) bearing against theside walls of the said socket I3 whereby the slide I4 is adapted to beturned or rotated on the base 88. Intermediate such bearing portions I8and I9 the projection is undercut or cut away to provide a portionhaving an inclined or tapered wall 80 of smallest diameter toward theupper end of the projection and tapering into the bearing portion I9.

Securing bolts 8I pass through radially disposed openings in the base86. These bolts are threaded for portions of their lengths and thementioned openings are partly threaded whereby the bolts may be threadedinwardly and outwardly, radially, of the base. The inner flat ends ofthese bolts 8I bear on the outer flat ends of binder pins BIa journaledin a reduced diameter portion Blb and entering the socket 13 at a pointto engage the inclined wall 89 of the projection 11. From this it willbe clear that on tightening of the bolts their inner end portions willforce the binder pins 8Ia against the wall portion 89 and with acam-like action will tend to draw the projection 11 into the socket I3.

The result of this action will be that the swivel slide 83 is drawn downtight against coverplate '18 which in turn is drawn tight against theupper side of the base 68. Thus the said slide portion will be heldagainst any casual movement, turning or otherwise, relative to base 66.On slight loosening of the radial bolts 8I the projection IT, and thusthe entire slide 14 may be turned relative to base 66. Preferably thecover plate I6 is provided with a mark 82 or the like to be read inconnection with the graduations on the upper central portion of base 66.It is noted with the described arrangement of the radial bolts 8I whenthey are tightened to secure the slide in any adjusted relation to thebase they have no tendency to disturb such adjustment. While four of theradially disposed bolts 8I have been shown in the drawings it will beunderstood that this number may be varied.

The cover plate I8 is a relatively stationary part of the slide I4 andis pinned or otherwise made rigid with swivel slide 83 as by a pin 16b.The relatively movable portion 84 of said slide may be reciprocated onswivel slide 83 as will appear. Part 84 bears downwardly on swivel slide83 at several spaced points as at 85, 86 and 81. Additionally it haslateral contact at 88 and provision for adjustment for wear between theparts is made by an adjustable tapered gib 89 7 adapted to be adjustedand held in adjusted positions by screws 99 and 9I.

A pair of side strips 92. and 93 are secured by screws 94 to the lowerlongitudinal edges of the movable slide part 84 and entering under thelower side edge portions of swivel slide 83 serve to assist in guidingmovements of the part 84 on said swivel slide and in addition preventany vertical movement of said part relative to the swivel slide. Part 84has relatively heavy end pieces 95 and 96 secured to its respective endsby screws 91 and these end pieces are located beyond the ends of theswivel slide 83.

Screws 98 secure closure plates 99 and I99 to the lower edges of thepieces 95 and 98 respectively and such plates extend from said piecestoward one and another and serve to prevent the entrance of dust intothe ways or bearing surfaces between part 84 and swivel slide 83. Asseen in Fig. 14 plate 99 is closing the spacebetween end piece 95 andthe adjacent end of cover plate I6 while plate I98 is entered over theother end portion of said cover plate I6. On movement of slide part 84toward the right in said figure plate I89 will be exposed and will serveto exclude dust from entering between end a 98 and the adjacent portionof bottom plate I8 while plate 99 will move in over the other endportion of the bottom plate.

Coil springs IIH disposed in sockets I92 in the swivel slide 83 bearagainst rods or plungers I03 bearing against the end'piece 95 andconstantly tend to maintain the slide part 84 in the positions of Figs.13, 14 and 15. A screw I94 adjustable through end 98 is adapted toengage a stop projection I on the swivel slide 83 whereby to limitmovement of part 84 by said coil springs. A look nut H96 is provided tosecure said screw after any adjustment thereof; A second screw I91 isthreaded through end piece and is adjustable therethrough and is adaptedto engage the adjacent end portion I08 of.

swivel slide 83 to limit movement of part 84 on said swivel slide inopposition to the coil springs IilI. Screw I9? is provided with a lockor jam nut I89 for securing it in adjusted position.

Means are provided for manually moving the slide part 84 against thetendency of the coil springs IOI and as will later appear the slide withslight modifications is adapted to be moved by a cam against thetendency of said springs when the slide is used in a profile grindingoperation. The manual means includes a lever IIO pivoted intermediateits ends at HI and at one end pivoted at 2 to the free end of a link II3 which in turn is anchored by a pivot II4 on a lug II5 supported byand disposed laterally of the bottom plate 16 of the slide.

Pivot III enters a slight boss IIS on one end portion of the upper slideof the slide part 84 and at opposite sides of said boss the part isprovided with bearing surfaces II'I. At times it is desirable to reversethe position of the lever H8 and to provide for the pivotal mounting ofthe lever at such times a boss H8 is provided on slide part 84 towardthe end thereof opposite that at which the boss I I8 is located.

, With the described construction (see Fig. 13 it will be clear thatonpulling of the free end of lever IIO toward the right the slide part 84will be moved on swivel slide 83 in opposition to the coil springs IOIcompressing the latter between the forward ends of the plungers I03 andthe inner ends of the sockets I02. ,On release of the pressure on thelever the springs will. act to return slide part 84 to normal positionwith screw I04 against stop I05. The swivel slide part 84 of each slideis provided on each longitudinal edge with a finished surface 284against which a "sine bar or the like may be used when adjusting theslide to various angular relationships with the table I1. I

When the slides are used in multiple, as in the present instance whereslide 15 is mounted on slide 14, it is sometimes necessary or at leastdesirable to lock one slide against any casual movement while the otherslide is being manipulated. The reasons for this will later appear. Tothe desired end, it is noted that swivel slide 83 is provided with acentral longitudinally extending inverted T slot H9 in which is locatedthe head of a bolt I extending through the upper side of the slide part84 and there provided with a nut I2I. Clearly bolt I 20 is movable withslide part 84 and this part may be secured in fixed relation to theswivel slide 83 on tightening of the nut I2I to clamp part 84 againstthe bearing surface portion 85 of swivel slide 83. Th nut may betightened to secure the parts against relative movement with the head ofbolt I20 in any position of adjustment along the length of the slot II9.

Slide part 84 is built up centrally on its upper side providing aportion I22 having a tapered opening or socket I23 therein andcorresponding exactly with the socket 13 in the base member 66. Aboutits outer edge portion I22 is graduated as shown at I24 in the mannerdescribed in connection with the Socket I23 is for the reception of theprojection 11 of another slide or a similar projection on another partas will appear. For the purpose of securing any such projection in thesocket and clamping any additional slide or other part against the upperedge of portion I22 four bolts I25 are threaded radially through suchportion I22 and these bolts are to function with pins I25a as and forthe purpose set forth when considering bolts 8| and pins 8Ia.

Mounted on slide 15 is a work head generally designated I26 shown moreparticularly in Figs. 7, 8, 9-, 10, 11, and 12- and comprising a bodyportion I21 having a lower annular flange-like portion I28. Centrallyfrom the lower side of portion I28 and concentric therewith depends aprojection I29 of the shape, size and construction of the projection 11at the-under side of slide 14' above described. Projection I29 hastheupper and lower annular bearing surfaces I30 and I31 and the inclinedsurface portion I32 corresponding with the portions 18', 19 and 80respectively of the projection 11.

In the present instance projection I29 is located in the socket I23opening through the upper side of the slide 15 and is clamped therein bythe radially extending bolts I25 of said slide whereby the head I26 ismounted on said slide 15. Head I26 is turnably adjustable relative toslide 15 on loosening of screws or bolts I25 and flange-- I28 of thehead is provided with a'mark I33 to be used in reading the graduationsI24 about the graduations of the part upper outer edge of the raisedportion I22 of the movable part of said slide.

Mounted on the upper side of body I21 is an electric motor I34. Saidbody is bifurcated in its upper portion whereby it comprises spacedsleeve-like portions I35 and I36. Internally sleeves I35 and I36 aretapered whereby they are of greatest diameter toward their outer endsand in each sleeve is an externally tapered bearing. member, suchmembers being numbered I31 and I38 respectively. Mounted by the bearingsI31 and I38 is a hardened, ground and seasoned spindle I39 at itsforward end mounting a chuck I40 for holding work I4I. A quill I42extends through the spindle I39 and at the end thereof opposite saidchuck is provided with a hand wheel or the like I43 for manipulating thequill to thereby open and close the chuck I40.

Externally tapered bearings I31 and I38 are longitudinally adjustable inthe sleeve I35 and I36 to compensate for wear. At its outer or for- Wardend bearing I38 abuts against a radial enlargement or flange I 44 on thespindle and a collar I45 backed by a threaded nut I45a on the spindleabuts against the outer or rear end portion of the bearing I31, Each ofsaid bearings is externally threaded toward each of its ends. An annularmember or nut I46 is threaded onto the outer end of bearing I38 andabuts against the forward end of sleeve I36 and includes a flange I41extending inwardly over the flange I44 on the spindle. This nut anchorsthe bearing I38 and in addition serves to assist in excluding dust andthe like from entering between the bearing and the sleeve and thebearing and the spindle.

In the bifurcation of the body I21 are a pair of ring nuts I48 and I49of which the former is threaded onto the inner end of bearing I38 andabuts against the inner end of the sleeve I36. Nut I49 is threaded ontothe inner end of bearing I31 and abuts against the inner end of sleeve I35. In addition nut I48 is provided in a side with an annular recess I50into which enters an annular bead I5I on the side of the nut I49. Awasher I52 of paper or other compressible material is located in thegroove I50 and is somewhat compressed therein by the bead I5I. With thisinterlocking arrangement the entrance of dust and the like to thespindle between the nuts I48 and I49 is prevented.

A nut I53 is threaded onto the outer or rear end portion of bearing I31and abuts against the outer or rear end of the sleeve I35. With thedescribed construction it will be seen that on loosening of nuts I46 andI53 and corresponding tightening of nuts I48 and I49 respectively thebearings I31 and I38 may be drawn inwardly in the sleeves I36 and I 35to compensate for any wear. Further with the described construction itwill be understood that provision has been made for the exclusion ofdirt and dust from the spindle. As shown the various ring nuts areprovided with spaced openings for engagement by a spanner wrench orother tool to be used in turn-ing the same. Asan additional precautioneach of the bearings I 31 and I38 is provided internally on the spindlebearing surfaces with right and left hand spiraled oil grooves I54 (seeFig. 12) so arranged as to feed oil toward'the ends of the bearings asthe spindle is revolved. This will serve to wash or flush some oil outover the flange I44. As the oil washes outwardly the inward movement ofdust or the like will be effectively prevented. Oil may be supplied tothe spindle in any suitable manner. Pins I55 are provided in the sleevelike portions I and I36 and engage longitudinal slots I5-5a in thebearings permitting longitudinal and preventing rotational movement whenadjusting the ring nuts I46, I48, I49 and I53.

A bracket I56 is secured to body I21 as by bolts I51 passing throughlongitudinally extending slots I56 in said bracket, With thisarrangement it will be clear that, within the limits of the lengths ofthe slots, the bracket I56 may be adjusted relative to the body I21. Atits rear end the bracket I55 supports a bearing means I59 rotatablysupporting a shaft I60 having stepped pulleys I6I and I62 fixed theretoto turn therewith. On the shaft of motor I34 is a stepped pulley I53 anda belt I64 drives the pulley I6I from the pulley I63.

Fixed on the rear end portion of spindle I39 is a stepped pulley I65 anda belt I66 drives said v stepped pulley I65 from the stepped pulley I62on the shaft with the pulley I6I Thus it will be seen that motor I34drives the spindle I39 and the chuck I40. By shifting the belts I64 andI66 to different steps of the pulleys various speeds may be imparted tosaid spindle and chuck, Any slack in the belts may be taken up byadjusting the bracket I56 to carry the pulleys IN and I62 away from thepulleys I63 and I65 and by sliding the motor I34 along slots I34a in themotor base either toward or away from the pulley I6I as is required tocomplete adjustment and finally securing the motor in position by boltsI34b. A control switch S is mounted on the forward portion of bracketI56.

Means are provided for holding the spindle I 39 and the chuck I againstturning movement while using the handwheel I43 with standard drawbackchucks or when using a spanner wrench to loosen or tighten the work I4Ithrough a chucking ring I400, which is necessary for larger work. Asshown the chuck I40 is slidably keyed by I401) to the spindle I39 inorder to make parts I65, I39, and I40 turn with one another. Pulley I65,fixed to the spindle, is provided with a series of openings or socketsI61 in its inner side. To an extension I68 of the sleeve I35 bolts I69secure a small bracket I10 slidably mounting a lock-bolt I'i'l having anend portion I12 adapted to enter any of the sockets I61 in the pulley. Acoil spring I13 tends to maintain said lock-bolt in a retractedpositionagainst an eccentric shaft H4 to the outer end of which is fixed a hubI15 carrying a cross pin or hand piece I16,

On turning of this hand piece in either direction the bolt I'sI isprojected to have its end portion I12 enter one of the sockets I61 tothereby lock the pulley I and the other parts against turning movementwhile the chucking ring M011 is being manipulated. When the eccentricshaft I14 is turned to a dead center position along the line of actionof bolt I1! the spring I13 is inefiective to retract the bolt, After anadjustment has been made the hand piece is manipulated to retract thebolt, As shaft I14 is moved back from a dead center position the springbecomes effective and completes return movement of the bolt, freeing thepulley, and retaining the bolt in retracted position out of the way ofthe pulley. At the left hand end of the bearing I31 an annular ringI-53a and a flange I531) extending outwardly are secured as b means of ascrew I530 to the nut I53. The ring I53a and the flange i531? enter acounter-bore 465a in the pulley I65. With this overlapping arrangementand a small amount of oil seepage from the end bearing I31 past theflange I53b tov the bottom-surface of. the revolving counterbore Iaaneffective seal is formed for the rotating bearing surfaces locatedwithin. V

In many instances the slide 15 will be identical with the slide 14.However, as here shown slide 15 is slightly modified since it is beingused for profile grinding. The modifications will be clear from Fig. 16wherein it will be noted that the stop bolts I04 and I01 have beenomitted and that a cam roller I" has replaced bolt I01 and that in theplace of bolt I04 another stud I18 has been threaded intoor otherwiseattached to the projection I05 of the swivel slide 83 and passesoutwardly of the slide through its end 96. On the outer portion of studI18 is a nut I19 adjustable on the stud to limit movement of the vslide. The purpose of this construction will appear in detail but hereit is noted that as the slide part 84 is moved on the swivel slide 83 byengagement of'roller I11 with a cam or otherwise, the'stud I18 remainsstationary with swivel slide 83 and 84 moves outwardly toward nut. I19.At the extreme of the movement I19 maybe tightened against the said endpiece of the :movable slide part and the latter held against the nut bylever I I0 as the table I1 is fed backby lever means 20. This'limitationof movement of 84 by nut I19 prevents the slide being moved to suchextent as to bring the other side of the work against the grinding wheeland, as the part: 84 is held against the nut by lever IIO the work isheld away from the grinding wheel during return movement of table I1.Thus all grinding may be done on the one stroke of the table and anyback lash or play in the parts will always be in the same direction. 7

On the bed I2 rearwardly of the head I26 is a. raised support I disposedon a surface I8I along which it is adjustable. In said surface is a V'Tslot I82 receiving theheadsof inverted T-bolts I83 passing through thebase I84 of said support I80 and also receiving elongated keys I85 asshown best in Fig. 4. Fixed on the upper side of support I80 is anysuitable cam I86. This cam is adjustably and removably secured on thesupport. Thus, the cam is provided with elongated slots 7 I81 throughwhich pass bolts I88 also threaded in the support. j 1

Suitable dust screens or covers I89 and I90 are disposed .above the camI86 and between the underside of the. cam mounting portion of supportI80 and the adjacent end portion of slide 15. On loosening of bolt I88the cam I86 maybe adjustedfon the support I80 and on loosening of boltsI83 the said support may be bodily adjusted along the surface I8I beingguided by the V-T slot I82.

Toward one end, (see Figs. 1, 2, 3, and 6) the machine bed is providedwith transversely or for-. wardly and rearwardly extending ways I9Ilocated in a plane slightly below that of the forward portion I92 ofsaid end of the bed. Slidable on the ways I9I is a carriage generallydesignated I03 and comprising a base portion I 94 having an undercut ordove-tail portion I95 movable in the ways. An adjustable gib I96 isprovided in the ways between the slide or carriage I93 and the bed I2.Said gib is provided with adjusting screws I96a threaded in and throughthe dovetail way I9I in the bed I2 to take up any play caused by wear ofthe dove-tail surfaces.

Carriage I93 is of some height and includes an upper forwardly directedhorn-like portion I91 under which the table I1 may pass. In its

